Title :
Accelerating the convergence of a decision-based algorithm for blind equalization of QAM signals
Author :
Filho, João Mendes ; Miranda, Maria D. ; Silva, Magno T M
Author_Institution :
Escola Politec., Univ. of Sao Paulo, São Paulo, Brazil
Abstract :
Recently, we proposed a decision-based algorithm for blind equalization that performs similarly to a supervised algorithm in steady-state, independently of the QAM order. Using this algorithm, the usual switching to the decision-directed mode may be avoided. Additionally, a low-cost scheme based on the neighborhood of the estimated symbol was used to improve its convergence rate. In this paper, we interpret this scheme from a probability density function fitting perspective. When the uncertainty on the estimated symbol is high, simulations show that the neighborhood plays an important role for speeding up the convergence. On the other hand, to ensure a low mean-square error, the neighborhood must be disregarded in steady-state.
Keywords :
blind equalisers; quadrature amplitude modulation; QAM signals; blind equalization; decision-based algorithm; decision-directed mode; low mean-square error; probability density function fitting perspective; supervised algorithm; Blind equalizers; Convergence; Estimation error; Quadrature amplitude modulation; Signal processing algorithms; Steady-state; Adaptive signal processing; blind equalizers; decision-directed algorithm; pdf fitting; quadrature amplitude modulation;
Conference_Titel :
Cognitive Information Processing (CIP), 2012 3rd International Workshop on
Conference_Location :
Baiona
Print_ISBN :
978-1-4673-1877-8
DOI :
10.1109/CIP.2012.6232897